Manhole



' Jan. 13, 1931. I c. A. GLAss 1,788,998

MANHOLE Filed Oct. 14. 1927 f .1, Illllllllll Y l INVENTOR 670??? /Z ATTORN EY Patented Jan. 13, 19317v Y yGiens-ron A. GLASS, or KANsAsoIrY, Missionar, Assieivon "ro KANSAS citrYfsTRnc- TURAL STEEL COMPANY, or` KANSAS oir'Y,`- irissouisr,A oonroae'rion or i sonni MANI-:OLE l Y Application mea october it,v 1927.- seriaino. 22e,125v.f-'

My invention relates to manhole closures for oil or like taiiksand more particularly to a structure of that character adapted for location in the side Wall of a tank of large v5, capacity Where it is subjected to extreme Viressures from contents of the tank' the Y. 5 principal object or the vinvention being to provide a gas and liquidtiglit closure, capa-V` ble of withstanding eXtreme pressures, but easily manipula-table to provide access to the tank.

In ordinary tank construction a ring and a cover plate are provided of cast iron or cast steel, and riveted at the factory to the particular plat-eV of the tank having the opening. A east manhole asseniblyis rela-- tively massive, both because of the requirement of strength to withstand pressure from a high head of oil in the tankand because ot the Wide web and ring iianges necessary to vprovide the means for fastening the cover to the ring; and which, when attacliedto a tank plate, presents a troublesome problem in transportation. Cast iron covers and frames moreover are more or less porous and likely to contain air holes, through which the oil or contents of the tank may leak and which may not be discovered until the tank is set up and supplied With oil. The extreme penetrability of oil requires therefore that covers and frames be .provided of dense solid material, to retain it..

Rolled steel pla-te has been used for covers; and manhole frames have been builtiip et' two or more rolled steel members Weldedftogetlier, the lattei' structure presenting un desirable features of cost and bulk. It is toV overcome these and other disadvantages of suchv ordinary construction, and to providev an 'eflicientmanhole closing means, that the present invention Was'designed.

In accomplishing the above and other objects ofthe invention I have provided iinproved details of structure. the preferred forms of which are illustrated in tlie aceom-` panying drawings, wherein: Y

'i Fig. l is a perspective View of a portion of a tank including a manhole closure constructed in-accordance withY my invention..

Fig is a ifertical section of such poi@ Fig. l.

Fig.

running centrally Referring in detail tothe drawings:l

`l designates the bottom of an oil storage tank, 2 a bottom flange vand 3 oneof `the plates riveted tothe bottoni iiange to constitutethe first course or ring ofthe Vtank structure.y A plate or slieet'oomprising plartf of 'the shell isillustrated for convenience Vbut the plate 8 maybe considered a flat plate in a side, top orL bottomivall of'a oontainer or partition, havingia` manhole opening vt-for the closure 'of which the present invention, including'jthe manhole, elements designated generally 5,-...1s designed. o

The. manhole closure comprises a. ringv G,V

having-an interior diameter corresponding tov that ofthev ma-nholefand having rivet openings 7 for receiving. rivets 8 whereby thering is secured to the outer face of the plate 3 of the tank; 9 designates a cover of greater diameter than the interior diameter of the ring to overlie the ringwhen the partsareassembled. ,Y Y

`Attached to the inner face'of the tank Wall and surrounding the manhole openingIv is av reinforcing plat-e 10, having an interior di,-v amleter ll greater than that of the opening and' substantially equal to the exterior diameter `of theiing to .provideA an exposed Wall.

vportion towhieh thering 6Y may be directly rivetedas shown in Figs. 2 land 3; the reinforcing VmemberV being secured to the tank plateby rivets 12. v i i rrlhefring G'isl preferably formed from rolled steel-fte Ycomprise an exterior annular recessedfportion orflange 13 through ,Whichthe attaching rivets -8v are projected andan outstanding. annularV rail ,14 for seating the v'Unirse f sterne? GCEEI 1 vf 3 is a sectional view yon thelines 3-3,

cover plate 9 and Vprovided `with threaded sockets l5 for receiving stud bolts 1G; a

'Gasket iY'being interposed between Ithe cover Aate and seat, andnuts 18 being provided ,"o theouter ends of the'stud bolts for se-y :cu ing the cover in rtight engagerneifity with 'fi ring. Y further provide as an important vfeature ef ring structure, the beveled outer edge fisio on the 1flange 13, whereby the canlking of the flange into sealing engagement with the shell plate is facilitated. The fact that the integral' ring member of my vstructure is "lsf formed of rolled steel provides for efficienti' caulking'ivith no liability of such breakage as may result from similar battering of cast members.l Y Y -The 'lange or recessed portionl is prom vided 'as described to'permit the use ot rela tively short rivets 8 for securing the yring to the tank shell plate Without sacrilice of tightness; Suficient depth forthe setting'ot the studs isA provided by the portionv 14 hav- .15 ing normal thickness.

.A clos r`re like that described, While smaller and lighter than those of Aordinary eonstruc- Y tion, is much less liablefto breakage and is more effective for preventing leakage of gases and cils. It further providesa struc` ture 'oil'cring less opportunity for damaging Contact by exterior objects and one which may be easily and quickly assembled and Vwherein the cover plate may be easily and quickly removed or replaced When access is tov be had to the tank from the manhole,

lhat I claim and desire to secure by Letters Patent is: I y

' l. In combination With a tankwallhaving-a manhole, a reinforcing plate on the inner face of the `Wall having .an opening concentric With but of greater diam-cterthan` the manhole, a ring attached to the outerV face totl the Wall having itsinner periphery registering with the manhole Opening and having its outer periphery substantially registering with the inner periphery Vot the reinforcing plate, means for securing the ring to the tank, and a cover removably attached l 40 to the ring. l I 7 i Y 'y 2. In co .ibination With atank Wall having a. manhole opening, a reinforcing plate attached to the inner/face ofr the Wall having an opening concentric AWith but vof greater' diameter' than the manhole opening, a ring attachedv to the outer face of the Wall about the manhole opening, including an inner body part provided With a cover seat having its inner periphery registering with the man'- hole opening,and an outer ange,vmeans extending through the'fiange and through the tank wall interiorily off the reinforcing plate v for attaching thering 'to the Wall, and a -v cover plate attached to the ring seat. Y In'testimo'ny whereof I affix my signature'.

CLIFTON GLASS. 

